Portable memory stick



FIG. 1 is an isometric view of a portable memory stick showing my new design;

FIG. 2 is a top view of thereof;

FIG. 3 is a front view of thereof;

FIG. 4 is a bottom view of thereof;

FIG. 5 is a back view of thereof;

FIG. 6 is a left side elevational view of thereof; and,

FIG. 7 is a right side elevational view of thereof. 

We claim the ornamental design for a portable memory stick, as shown and described. 